Fiberglass or gunite - high water table area coastal property on a canal Galveston Texas

[Texgirl]

We are building a coastal house on a canal around the Galveston texas area. The pool will be several feet from the bulk head. I have been told soil shifts more in this area and I know we have higher water table as most pools need to be built up out of the ground a few feet to handle high water table as well as high tides, storm flooding etc.

Gunite pools are far more popular in Texas than fiberglass. I have a gunite at my home but was considering fiberglass as this is a vacation home and I know fiberglass is easier maitenance as my dad had one etc.

My main concern is cracking etc.

Looking for advice on which is better for these conditions.

Thanks so much!

 

[YippeeSkippy]

I'd go with gunite. The reason I say that is you've got a known high water table, plus frequent enough episodes of freaky flood type rains. Many pools get overwhelmed with water and dirt and a gunite would be easiest to clean out without worrying about emptying the pool too far. You can NEVER empty a fibergass pool without a LOT of professional help.

Maddie

 

[Texas Splash]

Well, we've seen gunite shells pop out as well here on the forum, so whichever type you get, I think some serious ground engineering needs to be done. In your case, you might need additional drainage such as an underground well/sump pump system to help mitigate water pressure. Unless you are lucky enough to have a builder with such experience, get a 3rd party engineer familiar with the soil and water table in your area to determine the best way to handle this one..

 

[Dirk]

A high water table is an equal opportunity pool-destroyer, doesn't matter which kind of pool. Pat (Texas Splash) is giving you excellent advice. I'd be very wary of allowing a PB to fashion the proper solution for that without some sort of soil engineering specialist's oversight.

 

[YippeeSkippy]

My point was at least with gunite the owner could feel safe draining some of the pool, perhaps half?

We'd never suggest that with fiberglass.

 

[Dirk]

Certainly it would be safer to drain water out of a gunite pool than any other. Absolutely. And I don't know where the line would be drawn, but water displacement is a very powerful force. A pool surrounded by a high water table is basically a concrete ship. Think about those giant container ships with containers inside and outside, stacked 10 stories high! They float no problem. When a pool will float is dependent on how high the water table is relative to the water in the pool. You could safely drain 50% of the water if the table was below that level. 100% is the table was below the pool. But if the table is closer to the surface, then you wouldn't get away with half. Maybe not even 75% full. Check this out:




More to the point, something like this is what the OP might want to consider.

 

[gingrbredman]

The bottom diagram from above is very similar to what gets installed in fiberglass pool builds to prevent water from raising the shell out of the ground. You can see the very tall pipe in this picture of my build. I have the sump pump plugged into an outlet that is on the far side of the pool. Still have to check the pump regularly, just like a home sump, but these are standard for fiberglass installs.

 

[Texgirl]

I'd go with gunite. The reason I say that is you've got a known high water table, plus frequent enough episodes of freaky flood type rains. Many pools get overwhelmed with water and dirt and a gunite would be easiest to clean out without worrying about emptying the pool too far. You can NEVER empty a fibergass pool without a LOT of professional help.

Maddie

thank you so much!! I am back at the pool design quote etc... I really appreciate your response!

 

[Texgirl]

Well, we've seen gunite shells pop out as well here on the forum, so whichever type you get, I think some serious ground engineering needs to be done. In your case, you might need additional drainage such as an underground well/sump pump system to help mitigate water pressure. Unless you are lucky enough to have a builder with such experience, get a 3rd party engineer familiar with the soil and water table in your area to determine the best way to handle this one..

thank you!!! very good advice... I will be speaking to several builders next week so I will be sure to ask how they assess that situation.

 

[Texgirl]

A high water table is an equal opportunity pool-destroyer, doesn't matter which kind of pool. Pat (Texas Splash) is giving you excellent advice. I'd be very wary of allowing a PB to fashion the proper solution for that without some sort of soil engineering specialist's oversight.

wow.. thanks so much.. my neighbor has a pool... most of these pools are build partially out of the ground depending on the water table.. so they must have some way of assessing that.. I will get into detail with the builders on this subject.. thx again!!

 

[Texgirl]

The bottom diagram from above is very similar to what gets installed in fiberglass pool builds to prevent water from raising the shell out of the ground. You can see the very tall pipe in this picture of my build. I have the sump pump plugged into an outlet that is on the far side of the pool. Still have to check the pump regularly, just like a home sump, but these are standard for fiberglass installs.
View attachment 166268

hmmm so interesting!! Thank you for the info!